Extensive | steep pitched roof with roof curb

The ideal system for installing a maintenance-friendly extensive green roof with sedum blankets. Suitable for extensive vegetation on steep roofs with a slope between 25° and 45°, with roof curb.

In contrast to the structure of the steep pitched roof without a roof curb, this green roof does use substrate as a growing-medium layer. This system can also be used on roofs with a slope of up to 25 degrees and then it is possible to use plug plants and cuttings. In the steep pitched roof application, only vegetation blankets can be used. The choice of vegetation type, among other things, determines the substrate height. But the thickness of the substrate layer is also determined from the sum of the drainage layer and the growing-medium layer.

Technical data

Cuttings
Plug plants
Blankets
Recommended substrate height
approx. 90 mm
approx. 90 mm
approx. 80 mm
Total system height
approx. 90 mm
approx. 90 mm
approx. 110 mm
Total system weight, dry
approx. 95 kg/m²
approx. 95 kg/m²
approx. 110 kg/m²
Total weight, saturated
approx. 126 kg/m²
approx. 126 kg/m²
approx. 146 kg/m²
Total water buffering
approx. 31 l/m²
approx. 31 l/m²
approx. 36 l/m²
Run-off coefficients
Cs = 0.5 - 0.6
Cs = 0.5 - 0.6
Cs = 0.5 - 0.6
Type of vegetation
sedum, herbs
sedum, herbs
sedum, herbs
Slope in degrees
up to 25°
up to 25°
up to 45°

Example composition

Extensive vegetation (blankets, plug plants or cuttings)

ND ESW-80 Erosion Protection Grid (filled with substrate)

Root-resistant waterproofing membrane

from approx. 90 mm
from approx. 95 kg/m²
from approx. 126 kg/m²
from approx. 31 l/m²
Cs = 0.5 - 0.6
up to 25 ( and 45)°

Suitable system for steep roofs with a roof curb

The substrate must have good horizontal water drainage capacity and be filter stable. Because the mineral substrate is a natural product, the horizontal drainage capacity is difficult to calculate. Over time, the water drainage capacity decreases due to root penetration of the substrate layer and silting of the lower layers of the substrate.

The core for this steep pitched system is formed by the ND ESW-80 Erosion Protection Grid (filled with ND DGS-M Substrate Mineral). The ND SV-300 Protective Geotextile is installed between the grid and the waterproofing membrane to protect the latter.

With this system we recommend using a root-resistant waterproofing membrane to limit the risk of sliding. More information regarding erosion protection can be found in the FLL guidelines.

View our projects

Would you like to learn more about the possibilities of our innovative Nophadrain solutions for your project? Check out our existing projects here.

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Exact matches only
Filter by Product categorieën
Trafficable roofs
Green roofs
Water retention
Solar roofs
Erosion protection
Filter layer
Filter and drainage layer
Green roof packages
Growing medium layer
Inspection chambers
Roof edge / edge retaining profiles
Root barrier layer
Sedum cassettes
Separation, protection and slip layer
Vegetation layer
Vertical protection and drainage layer
Water buffering and water retention layer
Generic filters
Exact matches only
Filter by Product categorieën
Trafficable roofs
Green roofs
Water retention
Solar roofs
Erosion protection
Filter layer
Filter and drainage layer
Green roof packages
Growing medium layer
Inspection chambers
Roof edge / edge retaining profiles
Root barrier layer
Sedum cassettes
Separation, protection and slip layer
Vegetation layer
Vertical protection and drainage layer
Water buffering and water retention layer
Generic filters
Exact matches only
Filter by Product categorieën
Trafficable roofs
Green roofs
Water retention
Solar roofs
Erosion protection
Filter layer
Filter and drainage layer
Green roof packages
Growing medium layer
Inspection chambers
Roof edge / edge retaining profiles
Root barrier layer
Sedum cassettes
Separation, protection and slip layer
Vegetation layer
Vertical protection and drainage layer
Water buffering and water retention layer
Generic filters
Exact matches only
Filter by Product categorieën
Trafficable roofs
Green roofs
Water retention
Solar roofs
Erosion protection
Filter layer
Filter and drainage layer
Green roof packages
Growing medium layer
Inspection chambers
Roof edge / edge retaining profiles
Root barrier layer
Sedum cassettes
Separation, protection and slip layer
Vegetation layer
Vertical protection and drainage layer
Water buffering and water retention layer